The present invention relates to a vehicle having a hub assembly for a steerable wheel mounted for pivoting movement relative to an axle of the vehicle and a mudguard or fender for the wheel that is mounted for pivotal movement with the wheel hub assembly relative to the axle.
Agricultural tractors, such as those shown in U.S. Pat. No. 5,169,167 are powered for movement over the ground, and may be steered in a conventional manner by pivoting the front wheels relative to the front axle on which the front wheels are rotatably mounted about a king pin axis. Steering mechanisms are well known in the vehicle art, the geometry of which is such that the inboard front wheel on any particular turn is pivoted at a greater angle than the outboard front wheel. One skilled in the art will understand that tractor wheels are capable of being mounted on the tractor in various locations to permit the transverse spacing between the front, as well as the rear, wheels to be varied according to the spacing between the rows of crop material through which the tractor is to be run.
As taught in the aforementioned U.S. Pat. No. 5,169,167, the front wheels are often covered with a mudguard mechanism to prevent the spraying of material from the tire. The mudguard mechanisms may be mounted in an adjustable manner so that the mudguard can be properly positioned relative to the corresponding tire to provide the desired protection. Under certain conditions, such as when the front wheels are set at a relatively narrow transverse spacing, the mudguard mechanism, which projects generally upwards and rearward from the corresponding front wheel, can impact the chassis of the tractor during hard turns. This is particularly true for the inboard front wheel on a hard turn due to the greater angular rotation of the inboard wheel relative to the front axle.
Mechanisms have been devised to effect a pivotal rotation of the mudguard mechanism relative to the corresponding wheel to move the mudguard out of the way of the chassis during hard turns of the tractor. One such mechanism can be found in U.S. Pat. No. 5,074,573, which uses a spring to mount the mudguard to the corresponding front wheel. A stop member supported by the chassis engages the spring-loaded mudguard assembly to pivot the mudguard assembly relative to the inboard front wheel once the latter wheel has rotated a given amount. The mudguard spring returns the mudguard to its normal position after the front wheels have been rotated sufficiently to disengage the mudguard from the stop.
There is also known a mechanism that utilizes a spring-loaded mudguard mechanism in which the stop is eliminated so that the mudguard directly engages with the tractor chassis to effect a pivotal movement of the mudguard relative to the corresponding wheel. While both of these mechanisms serve to protect the mudguard and chassis from major damage due to a non-yielding mudguard, the rubbing engagement between the mudguard and the chassis requires special protective plates to prevent minor damage to the paint and finish of both the mudguard and the tractor chassis.
In order that the mudguard should not restrict the steering lock, it has further been proposed in FR-A-2.595.313, to provide a complex four-lever linkage anchored at different points on the hub assembly, on the mudguard and on the vehicle axle to cause the mudguard to pivot through a lesser angle than the hub assembly but about the same axis. In this case, the reliability of the linkage is suspect because of its many pivot points. It also sweeps through a large area as the wheel is steered, thus taking up a large amount of space.